On Fri, Jul 15, 2016 at 04:29:45PM +0200, Hans Petter Selasky wrote: H> On 07/15/16 11:28, Gleb Smirnoff wrote: H> > Author: glebius H> > Date: Fri Jul 15 09:28:32 2016 H> > New Revision: 302894 H> > URL: https://svnweb.freebsd.org/changeset/base/302894 H> > H> > Log: H> > Fix regression introduced by r302350. The change of return value for a H> > callout that wasn't scheduled at all was unintentional and yielded in H> > several panics. H> > H> > PR: 210884 H> > H> > Modified: H> > head/sys/kern/kern_timeout.c H> > H> > Modified: head/sys/kern/kern_timeout.c H> > ============================================================================== H> > --- head/sys/kern/kern_timeout.c Fri Jul 15 09:23:18 2016 (r302893) H> > +++ head/sys/kern/kern_timeout.c Fri Jul 15 09:28:32 2016 (r302894) H> > @@ -1381,7 +1381,7 @@ again: H> > CTR3(KTR_CALLOUT, "failed to stop %p func %p arg %p", H> > c, c->c_func, c->c_arg); H> > CC_UNLOCK(cc); H> > - return (cancelled); H> > + return (0); H> > } H> > H> > c->c_iflags &= ~CALLOUT_PENDING; H> > H> > H> H> Hi, H> H> I think r302894 and r302350 changes the return value of the following H> case, which is not described in the commit message? Is this also a H> regression? H> H> In this revision: H> > https://svnweb.freebsd.org/base/head/sys/kern/kern_timeout.c?view=markup&pathrev=296320 H> H> Assume we enter _callout_stop_safe() having the following assertions: H> H> (c->c_iflags & CALLOUT_PENDING) == 0 (satisfied) H> cc_exec_curr(cc, direct) != c (satisfied) H> H> Then we exit returning (-1). H> H> In this revision: H> > https://svnweb.freebsd.org/base/head/sys/kern/kern_timeout.c?view=markup&pathrev=296320#l1253 H> H> After your changes, entering the same function under the same conditions: H> H> cc_exec_curr(cc, direct) == c (not satisifed) H> (c->c_iflags & CALLOUT_PENDING) == 0 (satisfied) H> H> Then we exit returning (0). H> H> > https://svnweb.freebsd.org/base/head/sys/kern/kern_timeout.c?revision=302894&view=markup#l1384 H> H> If we call callout_stop() on a never scheduled callout, we now get a H> return value of 0 instead of -1, which by manual page definition is H> wrong ???? H> H> Am I wrong? Do others see this too?
You are right, the new -1 value was introduced by you and rrs@ in the commit: ------------------------------------------------------------------------ r290664 | rrs | 2015-11-10 06:49:32 -0800 (вт, 10 нояб. 2015) | 6 lines Add new async_drain to the callout system. This is so-far not used but should be used by TCP for sure in its cleanup of the IN-PCB (will be coming shortly). Sponsored by: Netflix Inc. Differential Revision: https://reviews.freebsd.org/D4076 ------------------------------------------------------------------------ So commit not only extended the KPI, but also changed it. And I missed that, using stable/10 version as reference. -- Totus tuus, Glebius. _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
